Preparation method and application of a Rosa roxburghii Tratt extract rich in vitamin C

Abstract

The present invention discloses a preparation method of a Rosa roxburghii Tratt extract rich in vitamin C, comprising the following steps: (1) washing fresh Rosa roxburghii Tratt fruits, and juicing them respectively after juicing or freezing; (2) taking the Rosa roxburghii Tratt juice, diluting it and passing it through an ultrafiltration membrane to obtain a filtrate; (3) taking the filtrate and concentrating it through a reverse osmosis membrane to obtain a concentrated Rosa roxburghii Tratt juice; (4) taking the concentrated Rosa roxburghii Tratt juice, adding ethanol, centrifuging to obtain a supernatant, and then concentrating and recovering the ethanol to obtain an alcohol-precipitated concentrated solution; (5) eluting the alcohol-precipitated concentrated solution on a macroporous resin, collecting the eluate and concentrating it to obtain an extract paste; (6) drying the extract paste to obtain a Rosa roxburghii Tratt extract rich in vitamin C, and also discloses the application of the extract. The preparation method of the present invention can make full use of fresh Rosa roxburghii Tratt fruits. Through the combination of various process steps, vitamin C is enriched. It is a natural vitamin C extract, and the antioxidant and whitening functions of the extract are significantly enhanced, providing a theoretical basis and application basis for promoting the development of the Rosa roxburghii Tratt industrial chain.

Description

Technical Field

[0001] The present invention belongs to the technical field of extraction of organic compounds, and particularly relates to a preparation method and application of a Rosa roxburghii Tratt extract rich in vitamin C. Background Art

[0002] Rosa roxburghii Tratt is the fruit of the plants Rosa roxburghii Tratt var. normalis Rehd. et Wils. and Rosa roxburghii Tratt in the Rosaceae family. It is a characteristic medicinal material of ethnic minorities in Guizhou and is included in the "Quality Standards of Chinese Medicinal Materials and Ethnic Medicinal Materials in Guizhou Province" (2003 edition) and has now been listed as a common food. Rosa roxburghii Tratt has different effects such as promoting digestion, strengthening the body, astringing essence and relieving diarrhea, contains various chemical components such as polyphenols, flavonoids, and triterpenoids, and is especially rich in vitamin C and SOD (superoxide dismutase). The content of vitamin C in the pulp ranks first among various fruits. The results of modern pharmacological studies show that Rosa roxburghii Tratt has various effects such as antioxidant, anti-tumor, anti-aging, and whitening and freckle-removing, and has potential health care application prospects.

[0003] At present, there are many studies on Rosa roxburghii Tratt extracts. As one of the key active ingredients of Rosa roxburghii Tratt, vitamin C has effects such as antioxidant, anti-aging, anti-scurvy, and treatment of anemia, and is widely used in pharmaceuticals, health products, foods, and beauty products. Preparing a Rosa roxburghii Tratt extract with a high content of vitamin C is directly related to the development of the Rosa roxburghii Tratt industry. However, the content of vitamin C in the Rosa roxburghii Tratt extracts obtained by the preparation methods disclosed in the prior art is relatively low, the process is complex, and the production cost is high, making it inapplicable to large-scale industrial production. For example: Patent applications CN106036270A, CN111700247B, CN109232487A, etc.

[0004] Therefore, there is an urgent need to establish a method for preparing a Rosa roxburghii Tratt extract with a high content of vitamin C to meet the application requirements of Rosa roxburghii Tratt extracts with a high content of vitamin C in industrial applications. Summary of the Invention

[0005] The present invention provides a preparation method and application of a Rosa roxburghii Tratt extract rich in vitamin C. The extracts obtained through processes such as freezing and juicing fresh Rosa roxburghii Tratt fruits, removing impurities by membrane filtration, reverse osmosis concentration, alcohol precipitation for impurity removal, and chromatography enrichment all contain a relatively high content of vitamin C, and their antioxidant and whitening effects are significantly enhanced.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A preparation method of a Rosa roxburghii Tratt extract rich in vitamin C, comprising the following steps:

[0008] (1) Wash fresh Rosa roxburghii Tratt fruits, freeze them, and juice them to obtain Rosa roxburghii Tratt juice;

[0009] (2) Take the Rosa roxburghii Tratt juice, dilute it with purified water, and pass it through an ultrafiltration membrane to obtain a filtrate;

[0010] (3) Take the filtrate and concentrate it with a reverse osmosis membrane to obtain concentrated Rosa roxburghii Tratt juice;

[0011] (4) Take the concentrated Rosa roxburghii Tratt juice, add ethanol, stir well, let it stand at low temperature, centrifuge to obtain the supernatant, and recover ethanol by controlling the vacuum degree and concentration temperature of the supernatant to obtain an ethanol precipitation concentrated solution;

[0012] (5) Load the ethanol precipitation concentrated solution onto macroporous resin, elute with purified water and ethanol-containing aqueous solution, collect the eluate, and concentrate to obtain an extract paste;

[0013] (6) Dry the extract paste to obtain a Rosa roxburghii Tratt extract rich in vitamin C.

[0014] The preparation method of the aforementioned Rosa roxburghii Tratt extract rich in vitamin C includes the following steps:

[0015] (1) Wash the fresh Rosa roxburghii Tratt fruits, freeze them at -4 to -20 °C for more than 24 hours, take out the frozen fresh Rosa roxburghii Tratt fruits, after thawing, juice them at a pressure of 3 to 7 kg for 0.5 to 1.5 hours, and filter to obtain Rosa roxburghii Tratt juice; Freezing and then thawing before juicing is more conducive to the dissolution of vitamin C and can improve the content of vitamin C in the finished product;

[0016] (2) Take the Rosa roxburghii Tratt juice, dilute it with 1 to 7 times the volume of purified water of the Rosa roxburghii Tratt juice, and filter it with a 10 - 100KD ultrafiltration membrane to obtain a filtrate. Ultrafiltration membrane filtration can effectively remove impurities in the Rosa roxburghii Tratt juice, especially macromolecular substances;

[0017] (3) Take the filtrate, control the pressure at 1 to 6 kg, and concentrate it with a reverse osmosis membrane to obtain concentrated Rosa roxburghii Tratt juice. Reverse osmosis membrane filtration removes most of the water in the Rosa roxburghii Tratt juice, which is beneficial for ethanol precipitation;

[0018] (4) Take the concentrated Rosa roxburghii Tratt juice, add 8 to 12 times the mass of 80 - 95% ethanol, stir well, let it stand at 2 to 8 °C for 10 to 16 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure with a vacuum degree of 0.08 to 0.09 mpa and a concentration temperature of 40 to 55 °C to obtain an ethanol precipitation concentrated solution; Ethanol precipitation can effectively remove substances insoluble in ethanol in the Rosa roxburghii Tratt juice and further remove impurities;

[0019] (5) Load the ethanol precipitation concentrated solution onto macroporous resins such as AB - 8, HPD - 100, D101, etc., use purified water and 5 - 30% ethanol-containing aqueous solution as eluents, and concentrate the eluate to an extract paste with a relative density of 1.10 to 1.20. Using macroporous resin chromatography can enrich vitamin C;

[0020] (6) The extract paste is dried by vacuum drying: vacuum degree 0.08 to 0.09 mpa, drying temperature 40 to 55 °C; or freeze-drying: pre-freezing temperature: -10 to 50 °C, vacuum degree 10 to 30 Pa, water trap temperature 35 to 45 °C, shelf temperature -10 to 10 °C to obtain a Rosa roxburghii Tratt extract rich in vitamin C.

[0021] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (1), the freezing temperature is -12°C, the juice extraction pressure is 5 kg, and the juice extraction time is 1 hour.

[0022] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (2), it is diluted with purified water at 4 times the volume of the Rosa roxburghii Tratt juice and filtered through a 50KD membrane.

[0023] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (3), the membrane concentration pressure is controlled at 3 kg.

[0024] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (4), 10 times the amount of 85% ethanol is used for alcohol precipitation at 6°C for 13 hours. The vacuum degree for ethanol recovery is 0.085 mpa, and the concentration temperature is 43°C.

[0025] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (5), the macroporous resin is HPD-100, and it is eluted with purified water as the eluent. The purified water eluent is concentrated to an extract paste with a relative density of 1.15.

[0026] The preparation method of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C. In step (6), the extract paste is vacuum dried. The vacuum degree is 0.085 mpa, and the drying temperature is 47°C.

[0027] For the Rosa roxburghii Tratt extract rich in vitamin C prepared by any of the above preparation methods, its vitamin C content ≥ 50%.

[0028] Application of the above-mentioned Rosa roxburghii Tratt extract rich in vitamin C in antioxidant and whitening functions.

[0029] The beneficial technical effects of the present invention are:

[0030] 1. The present invention provides a preparation method of a Rosa roxburghii Tratt extract rich in vitamin C. Through steps such as freezing and juicing fresh Rosa roxburghii Tratt fruits, ultrafiltration membrane filtration for impurity removal, reverse osmosis membrane concentration, alcohol precipitation for impurity removal, macroporous resin chromatography enrichment, and drying, a high-content natural Rosa roxburghii Tratt extract rich in vitamin C is obtained. The vitamin C content in the Rosa roxburghii Tratt extract of the present invention is higher than 50%.

[0031] 2. After the fresh Rosa roxburghii fruits are frozen and then thawed before juicing, it is beneficial to the dissolution of vitamin C. The macromolecular impurities in the Rosa roxburghii juice are filtered out by an ultrafiltration membrane, and the dissolved salts and other substances in the Rosa roxburghii juice are removed by a reverse osmosis membrane. The alcohol precipitation step further removes the substances insoluble in alcohol in the Rosa roxburghii juice. The macroporous resin further enriches vitamin C. According to the physical and chemical properties of the substances to be removed, specific combinations of process parameters and the sequence of process steps are experimentally screened to obtain the Rosa roxburghii extract with high vitamin C content of the present invention. The process steps are simple and the operation is convenient, which is suitable for large-scale industrial production.

[0032] 3. The finished product of the present invention, the Rosa roxburghii extract rich in vitamin C, the research results of the in vitro antioxidant function test and the whitening efficacy test show that its antioxidant and whitening effects are significantly enhanced. The present invention provides technical support for the application of vitamin C in Rosa roxburghii in medicines, health products, foods and beauty products, and provides a theoretical and application basis for the development of the Rosa roxburghii industry and the big health industry. Detailed implementation mode

[0033] Example 1:

[0034] A preparation method of a Rosa roxburghii extract rich in vitamin C:

[0035] (1) Wash the fresh Rosa roxburghii fruits, freeze them at -4°C for more than 24 hours, take out the frozen fresh Rosa roxburghii fruits, after thawing, juice them under a pressure of 3 kg for 0.5 hour, and filter to obtain Rosa roxburghii juice;

[0036] (2) Take the Rosa roxburghii juice obtained in step (1), dilute it with purified water with a volume 1 time that of the Rosa roxburghii juice, and filter it with a 10KD ultrafiltration membrane to obtain a filtrate;

[0037] (3) Take the filtrate obtained in step (2), control the pressure to be 1 kg, and concentrate it with a reverse osmosis membrane to obtain concentrated Rosa roxburghii juice;

[0038] (4) Take the concentrated Rosa roxburghii juice obtained in step (3), add 8 times the mass of 80% ethanol, stir well, place it at 2°C for 10 hours, centrifuge to take the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.08 mpa, and the concentration temperature is 55°C to obtain an alcohol precipitation concentrated solution;

[0039] (5) Take the alcohol precipitation concentrated solution obtained in step (4) and load it onto AB-8 macroporous resin, elute it with purified water as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.10;

[0040] (6) Take the extract paste obtained in step (5) and perform vacuum drying: the vacuum degree is 0.08 mpa, and the drying temperature is 55°C to obtain a Rosa roxburghii extract rich in vitamin C.

[0041] The vitamin C content of the obtained Rosa roxburghii extract rich in vitamin C is 51.52%.

[0042] Example 2:

[0043] A preparation method of a rose roxbunghii extract rich in vitamin C:

[0044] (1) Wash the fresh rose roxbunghii fruits, freeze them at -20°C for more than 24 hours, take out the frozen fresh rose roxbunghii fruits, after thawing, juice them at a pressure of 7 kg for 1.5 hours, and filter to obtain rose roxbunghii juice;

[0045] (2) Take the rose roxbunghii juice obtained in step (1), dilute it with purified water 7 times the volume of the rose roxbunghii juice, and filter it through a 100KD ultrafiltration membrane to obtain a filtrate;

[0046] (3) Take the filtrate obtained in step (2), control the pressure at 6 kg, and concentrate it with a reverse osmosis membrane to obtain a concentrated rose roxbunghii juice;

[0047] (4) Take the concentrated rose roxbunghii juice obtained in step (3), add 95% ethanol with a mass 10 times that of the concentrated rose roxbunghii juice, stir well, place it at 8°C for 16 hours, centrifuge to take the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.09 mpa, and the concentration temperature is 40°C, to obtain an ethanol precipitation concentrated solution;

[0048] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto macroporous resins such as D101, elute it with an ethanol aqueous solution containing 5% ethanol as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.20;

[0049] (6) Take the extract paste obtained in step (5) and perform vacuum drying: the vacuum degree is 0.09 mpa, and the drying temperature is 40°C, to obtain a rose roxbunghii extract rich in vitamin C.

[0050] The vitamin C content of the obtained rose roxbunghii extract rich in vitamin C is 53.78%.

[0051] Example 3:

[0052] A preparation method of a rose roxbunghii extract rich in vitamin C:

[0053] (1) Wash the fresh rose roxbunghii fruits, freeze them at -12°C for more than 24 hours, take out the frozen fresh rose roxbunghii fruits, after thawing, juice them at a pressure of 5 kg for 1.0 hour, and filter to obtain rose roxbunghii juice;

[0054] (2) Take the rose roxbunghii juice obtained in step (1), dilute it with purified water 4 times the volume of the rose roxbunghii juice, and filter it through a 50KD ultrafiltration membrane to obtain a filtrate;

[0055] (3) Take the filtrate obtained in step (2), control the pressure at 3 kg, and concentrate it with a reverse osmosis membrane to obtain a concentrated rose roxbunghii juice;

[0056] (4) Take the Rosa roxburghii Tratt concentrated juice obtained in step (3), add ethanol with a mass 12 times that of the concentrated juice and with a concentration of 87%, stir well, let stand at 5°C for 13 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.085 mpa, and the concentration temperature is 47°C, to obtain an ethanol precipitation concentrated solution;

[0057] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto HPD-100 macroporous resin, elute with an ethanol aqueous solution with an ethanol content of 30% as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.15;

[0058] (6) Take the extract paste obtained in step (5) and perform vacuum drying: the vacuum degree is 0.085 mpa, and the drying temperature is 47°C, to obtain a Rosa roxburghii Tratt extract rich in vitamin C.

[0059] The vitamin C content of the obtained Rosa roxburghii Tratt extract rich in vitamin C is 53.46%.

[0060] Example 4:

[0061] A preparation method of a Rosa roxburghii Tratt extract rich in vitamin C:

[0062] (1) Wash the fresh Rosa roxburghii Tratt fruits, freeze them at -15°C for more than 24 hours, take out the frozen fresh Rosa roxburghii Tratt fruits, after thawing, juice them under a pressure of 6 kg for 1.2 hours, and filter to obtain Rosa roxburghii Tratt juice;

[0063] (2) Take the Rosa roxburghii Tratt juice obtained in step (1), dilute it with purified water with a volume 5 times that of the Rosa roxburghii Tratt juice, and filter it through a 90KD ultrafiltration membrane to obtain a filtrate;

[0064] (3) Take the filtrate obtained in step (2), control the pressure to be 5 kg, and concentrate it with a reverse osmosis membrane to obtain Rosa roxburghii Tratt concentrated juice;

[0065] (4) Take the Rosa roxburghii Tratt concentrated juice obtained in step (3), add ethanol with a mass 10 times that of the concentrated juice and with a concentration of 83%, stir well, let stand at 6°C for 12 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.09 mpa, and the concentration temperature is 47°C, to obtain an ethanol precipitation concentrated solution;

[0066] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto HPD-100 macroporous resin, elute with an ethanol aqueous solution with an ethanol content of 17% as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.15;

[0067] (6) Take the extract paste obtained in step (5) and perform freeze-drying: the pre-freezing temperature is -10°C, the vacuum degree is 10 Pa, the temperature of the water trap is 35°C, and the temperature of the baffle is -10°C, to obtain a Rosa roxburghii Tratt extract rich in vitamin C.

[0068] The vitamin C content of the obtained Rosa roxburghii Tratt extract rich in vitamin C is 54.17%.

[0069] Example 5:

[0070] A preparation method of rose roxburghii tratt extract rich in vitamin C:

[0071] (1) Wash the fresh rose roxburghii tratt fruits, freeze them at -10°C for more than 24 hours. Take out the frozen fresh rose roxburghii tratt fruits, after thawing, juice them at a pressure of 4 kg for 1.0 hour, and filter to obtain rose roxburghii tratt juice;

[0072] (2) Take the rose roxburghii tratt juice obtained in step (1), dilute it with purified water with a volume 3 times that of the rose roxburghii tratt juice, and filter it through a 60KD ultrafiltration membrane to obtain a filtrate;

[0073] (3) Take the filtrate obtained in step (2), control the pressure to 6 kg, and concentrate it with a reverse osmosis membrane to obtain rose roxburghii tratt concentrated juice;

[0074] (4) Take the rose roxburghii tratt concentrated juice obtained in step (3), add 8 times the mass of 80% ethanol, stir well, place it at 2°C for 10 hours, centrifuge to take the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.08 mpa, and the concentration temperature is 40°C to obtain an ethanol precipitation concentrated solution;

[0075] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto macroporous resins such as D101, elute it with purified water as the eluent, and concentrate the eluate to an extract ointment with a relative density of 1.10;

[0076] (6) Take the extract ointment obtained in step (5) and perform freeze-drying: the pre-freezing temperature is 50°C, the vacuum degree is 30 Pa, the water trap temperature is 40°C, and the partition temperature is 0°C to obtain rose roxburghii tratt extract rich in vitamin C.

[0077] The vitamin C content of the obtained rose roxburghii tratt extract rich in vitamin C is 52.17%.

[0078] Example 6:

[0079] A preparation method of rose roxburghii tratt extract rich in vitamin C:

[0080] (1) Wash the fresh rose roxburghii tratt fruits, freeze them at -8°C for more than 24 hours. Take out the frozen fresh rose roxburghii tratt fruits, after thawing, juice them at a pressure of 3 kg for 0.5 hour, and filter to obtain rose roxburghii tratt juice;

[0081] (2) Take the rose roxburghii tratt juice obtained in step (1), dilute it with purified water with a volume 5 times that of the rose roxburghii tratt juice, and filter it through a 100KD ultrafiltration membrane to obtain a filtrate;

[0082] (3) Take the filtrate obtained in step (2), control the pressure to 3 kg, and concentrate it with a reverse osmosis membrane to obtain rose roxburghii tratt concentrated juice;

[0083] (4) Take the Rosa roxburghii Tratt concentrated juice obtained in step (3), add 10 times the mass of 95% ethanol, stir well, let it stand at 8°C for 16 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.09 mpa, and the concentration temperature is 55°C to obtain the ethanol precipitation concentrated liquid;

[0084] (5) Take the ethanol precipitation concentrated liquid obtained in step (4) and load it onto AB-8 macroporous resin, elute with an ethanol aqueous solution containing 5% ethanol as the eluent, and concentrate the eluate to an extract extract with a relative density of 1.20;

[0085] (6) Take the extract extract obtained in step (5) and perform freeze-drying: the pre-freezing temperature is 20°C, the vacuum degree is 20 Pa, the water trap temperature is 45°C, and the partition temperature is 10°C to obtain the Rosa roxburghii Tratt extract rich in vitamin C.

[0086] The vitamin C content of the obtained Rosa roxburghii Tratt extract rich in vitamin C is 50.85%.

[0087] Example 7:

[0088] A preparation method of Rosa roxburghii Tratt extract rich in vitamin C:

[0089] (1) Wash the fresh Rosa roxburghii Tratt fruits, freeze them at -14°C for more than 24 hours, take out the frozen fresh Rosa roxburghii Tratt fruits, after thawing, juice them at a pressure of 5 kg for 1.1 hours, and filter to obtain Rosa roxburghii Tratt juice;

[0090] (2) Take the Rosa roxburghii Tratt juice obtained in step (1), dilute it with 5 times the volume of purified water of the Rosa roxburghii Tratt juice, and filter it through a 40KD ultrafiltration membrane to obtain the filtrate;

[0091] (3) Take the filtrate obtained in step (2), control the pressure to 4 kg, and concentrate it with a reverse osmosis membrane to obtain Rosa roxburghii Tratt concentrated juice;

[0092] (4) Take the Rosa roxburghii Tratt concentrated juice obtained in step (3), add 12 times the mass of 87% ethanol, stir well, let it stand at 5°C for 13 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.085 mpa, and the concentration temperature is 47°C to obtain the ethanol precipitation concentrated liquid;

[0093] (5) Take the ethanol precipitation concentrated liquid obtained in step (4) and load it onto HPD-100 macroporous resin, elute with an ethanol aqueous solution containing 30% ethanol as the eluent, and concentrate the eluate to an extract extract with a relative density of 1.15;

[0094] (6) Take the extract extract obtained in step (5) and perform vacuum drying: the vacuum degree is 0.085 mpa, and the drying temperature is 47°C to obtain the Rosa roxburghii Tratt extract rich in vitamin C.

[0095] The vitamin C content of the obtained Rosa roxburghii Tratt extract rich in vitamin C is 53.92%.

[0096] Example 8:

[0097] A method for preparing a rose roxburghii tratt extract rich in vitamin C:

[0098] (1) Wash the fresh rose roxburghii tratt fruits, freeze them at -20°C for more than 24 hours. Take out the frozen fresh rose roxburghii tratt fruits, after thawing, juice them at a pressure of 5 kg for 0.8 hours, and filter to obtain rose roxburghii tratt juice;

[0099] (2) Take the rose roxburghii tratt juice obtained in step (1), dilute it with purified water with a volume 6 times that of the rose roxburghii tratt juice, and filter it through a 70KD ultrafiltration membrane to obtain a filtrate;

[0100] (3) Take the filtrate obtained in step (2), control the pressure at 4 kg, and concentrate it with a reverse osmosis membrane to obtain rose roxburghii tratt concentrated juice;

[0101] (4) Take the rose roxburghii tratt concentrated juice obtained in step (3), add 95% ethanol with a mass 10 times that of the rose roxburghii tratt concentrated juice, stir well, place it at 8°C for 16 hours, centrifuge to take the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.084 mpa, and the concentration temperature is 43°C, to obtain an ethanol precipitation concentrated solution;

[0102] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto AB-8 macroporous resin, elute it with an ethanol aqueous solution with an ethanol content of 17% as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.10;

[0103] (6) Take the extract paste obtained in step (5) and perform freeze-drying: the pre-freezing temperature is 25°C, the vacuum degree is 23 Pa, the water trap temperature is 42°C, and the baffle temperature is 5°C, to obtain a rose roxburghii tratt extract rich in vitamin C.

[0104] The vitamin C content of the obtained rose roxburghii tratt extract rich in vitamin C is 55.35%.

[0105] Example 9:

[0106] A method for preparing a rose roxburghii tratt extract rich in vitamin C:

[0107] (1) Wash the fresh rose roxburghii tratt fruits, freeze them at -12°C for more than 24 hours. Take out the frozen fresh rose roxburghii tratt fruits, after thawing, juice them at a pressure of 5 kg for 1.0 hour, and filter to obtain rose roxburghii tratt juice;

[0108] (2) Take the rose roxburghii tratt juice obtained in step (1), dilute it with purified water with a volume 4 times that of the rose roxburghii tratt juice, and filter it through a 50KD ultrafiltration membrane to obtain a filtrate;

[0109] (3) Take the filtrate obtained in step (2), control the pressure at 3 kg, and concentrate it with a reverse osmosis membrane to obtain rose roxburghii tratt concentrated juice;

[0110] (4) Take the Rosa roxburghii Tratt concentrated juice obtained in step (3), add ethanol at 85% by mass 10 times that of the juice, stir well, let it stand at 6°C for 13 hours, centrifuge to obtain the supernatant, and concentrate the supernatant under reduced pressure to recover ethanol: the vacuum degree is 0.085 mpa, and the concentration temperature is 43°C to obtain the ethanol precipitation concentrated solution;

[0111] (5) Take the ethanol precipitation concentrated solution obtained in step (4) and load it onto HPD-100 macroporous resin, elute with purified water as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.15;

[0112] (6) Take the extract paste obtained in step (5) and perform vacuum drying: the vacuum degree is 0.085 mpa, and the drying temperature is 47°C to obtain the Rosa roxburghii Tratt extract rich in vitamin C.

[0113] The vitamin C content of the obtained Rosa roxburghii Tratt extract rich in vitamin C is 57.46%.

[0114] Example 10:

[0115] Application of the Rosa roxburghii Tratt extract rich in vitamin C:

[0116] The Rosa roxburghii Tratt extract rich in vitamin C obtained in Examples 1-9 can be directly used as raw materials for antioxidant and whitening functional products.

[0117] The method for determining the content of ascorbic acid (vitamin C) in the above Rosa roxburghii Tratt extract rich in vitamin C (refer to the national food safety standard Determination of Ascorbic Acid in Foods (Standard No.: GB 5009.86-2016)) is as follows:

[0118] 1. Determination of vitamin C content

[0119] 1.1 Chromatographic conditions:

[0120] Chromatographic column: C18 column, column length 250 mm, inner diameter 4.6 mm, particle size 5 μm, or a chromatographic column with equivalent performance; Detector: Diode array detector or ultraviolet detector; Mobile phase: A: 6.8 g of potassium dihydrogen phosphate and 0.91 g of cetyltrimethylammonium bromide, dissolved in water and made up to 1 L (adjust the pH to 2.5 - 2.8 with phosphoric acid); B: 100% methanol. Mix according to A∶B = 98:2, filter through a 0.45 μm filter membrane, and perform ultrasonic degassing; Flow rate: 0.7 mL / min; Detection wavelength: 245 nm; Column temperature: 25°C; Injection volume: 20 μL.

[0121] 1.2 Preparation of the reference vitamin C solution:

[0122] 1.2.1 L(+)-Ascorbic acid standard stock solution (1.000 mg / mL): Accurately weigh 0.01 g of L(+)-ascorbic acid standard product (accurate to 0.01 mg), and make up to 10 mL with 20 g / L metaphosphoric acid solution.

[0123] 1.2.2 D(-)-Ascorbic Acid Standard Stock Solution (1.000 mg / mL): Accurately weigh 0.01 g of D(-)-ascorbic acid standard (accurate to 0.01 mg), and make up the volume to 10 mL with 20 g / L metaphosphoric acid solution.

[0124] 1.2.3 Ascorbic Acid Mixed Standard Series Working Solutions: Pipette 0 mL, 0.05 mL, 0.50 mL, 1.0 mL, 2.5 mL, 5.0 mL of L(+)-ascorbic acid and D(-)-ascorbic acid standard stock solutions respectively, and make up the volume to 100 mL with 20 g / L metaphosphoric acid solution. The concentrations of L(+)-ascorbic acid and D(-)-ascorbic acid in the standard series working solutions are 0 μg / mL, 0.5 μg / mL, 5.0 μg / mL, 10.0 μg / mL, 25.0 μg / mL, 50.0 μg / mL respectively. Prepare before use.

[0125] 1.3 Preparation of Sample Solution: Weigh about 0.5 g - 2 g (accurate to 0.001 g) of homogenized sample, or pipette 2 mL - 10 mL of liquid sample [so that the taken sample contains about 0.03 mg - 6 mg of L(+)-ascorbic acid] into a 50 mL beaker, transfer the sample to a 100 mL volumetric flask with 20 g / L metaphosphoric acid solution, shake to dissolve and make up the volume. Shake well, centrifuge at 4000 r / min for 5 min, pipette 1 mL of the supernatant into a 10 mL volumetric flask, dilute to the mark with 20 g / L metaphosphoric acid solution, shake well, filter through a 0.45 μm aqueous phase filter membrane, and the filtrate is for determination.

[0126] 1.4 Determination Method: Pipette 10 μL of the reference solution and the sample solution respectively, inject into the liquid chromatograph, calculate, and obtain the result.

[0127] 1.5 Comparison of Vitamin C in Rosa roxburghii Tratt Extract Rich in Vitamin C, see Table 1.

[0128] Table 1 Comparison Table of Vitamin C in Rosa roxburghii Tratt Juice and Rosa roxburghii Tratt Extract Rich in Vitamin C

[0129]

[0130] It can be seen that compared with the dry powder of Rosa roxburghii Tratt juice prepared by direct pressing and drying, the vitamin C content in the dry powder of Rosa roxburghii Tratt extract rich in vitamin C of the present invention has been greatly improved, breaking through the upper limit of the vitamin C content in natural Rosa roxburghii Tratt juice. The vitamin C content in the dry powder of Rosa roxburghii Tratt extract rich in vitamin C of the present invention has increased by 257.50% compared with the vitamin C content in natural Rosa roxburghii Tratt juice.

[0131] Conclusion on Comparing with the Existing Technology for Preparing Vitamin C:

[0132] Comparative Example 1:

[0133] Method source: The method of Comparative Document 1 "CN106036270A A method for concentrating natural vitamin C from Rosa roxburghii Tratt" is adopted, and the steps are as follows:

[0134] (1) Low-temperature cleaning: Put fresh Rosa roxburghii Tratt fruits into a two-stage cleaning tank. Remove sand, floating leaves, and rotten fruits to obtain clean Rosa roxburghii Tratt fruits at a temperature of 15 - 20 degrees. The purpose of the two-stage cleaning is that the water in the first stage is for primary washing and needs to be discharged; the water in the second stage is for fine washing, needs to be filtered and recycled, and the central temperature of the Rosa roxburghii Tratt fruits is controlled.

[0135] (2) Low-temperature oxygen-isolated crushing and juicing: Install a paddle-type pulper above the feed inlet of the press, and the whole is sealed and insulated. Introduce carbon dioxide at the bottom of the equipment, use the feed inlet of the pulper as the exhaust port to remove oxygen in the equipment, and keep the whole equipment at a slightly positive pressure (10 - 100 Pa). The whole equipment has a heat-insulating layer, and the treatment time is 5 minutes to ensure that the material temperature is 20 - 25 degrees.

[0136] (3) Removing tannins in a vacuum tank: The squeezed juice is sprayed into the vacuum tank for temporary storage (relative vacuum degree -90 to -20 KPa). Add 0.1 - 1% deacetylated chitosan (meeting the food additive use standard of GB2760) to the vacuum tank, mix and let it stand for 5 - 30 minutes to combine with tannins and precipitate. Filter out the tannins through a plate-and-frame filter press with diatomaceous earth as the filter aid. The setting of the vacuum tank is to remove the air contained in the Rosa roxburghii Tratt pulp and avoid the oxygen in it from destroying vitamin C. The temperature is about 20 - 25 degrees at this time.

[0137] (4) Microfiltration: Microfilter through a 0.1 - 0.5 micron ceramic membrane to obtain clarified juice. In this process, microfiltration also plays a role in removing bacteria and other microorganisms, preventing the membrane concentration system from being contaminated with bacteria, and ensuring the product's hygiene index. The temperature is about 20 - 30 degrees at this time.

[0138] (5) Reverse osmosis membrane concentration: The clarified juice enters the membrane concentration system. The membrane material is a RO reverse osmosis membrane, and a polyamide composite membrane with high low-temperature flux is selected. The operating temperature is 25 - 35 degrees, and the operating pressure is 5 - 25 MPa. Concentrated juice with 64% solids (equivalent to 8-fold concentration) is obtained. Considering the preservation of vitamin C, the concentrated juice is sealed in bags and stored in a -18-degree cold storage.

[0139] Conclusion: In the preparation process, the cold processing and oxygen-isolated technology have high requirements for equipment and high costs, are not suitable for application in large-scale industrial production, and the vitamin C content in the Rosa roxburghii Tratt concentrated juice prepared by this method is 18%, which is relatively low. Therefore, this method is not suitable for enriching vitamin C.

[0140] Comparative Example 2:

[0141] Method source: The method of Comparative Document 2 "CN111700247B A Rosa roxburghii powder rich in vitamin C and its preparation method" is adopted, and the steps are as follows:

[0142] (1) Juice fresh Rosa roxburghii to obtain Rosa roxburghii juice;

[0143] (2) Transfer the Rosa roxburghii juice to a fermentation tank, add 0.3% activated Saccharomyces cerevisiae, set the temperature at 25 - 40 °C, stir and ferment for 4 h to obtain the fermented Rosa roxburghii juice;

[0144] (3) Filter the fermentation broth with a 250 - mesh filter cloth, and then filter the filtrate with a ceramic membrane with an 80 - nm filter element inside, and collect the filtrate for standby;

[0145] (4) Vacuum - concentrate the filtered Rosa roxburghii juice. The vacuum degree for vacuum concentration is - 0.04 MPa, and the temperature is 45 - 75 °C. Concentrate until the solid content is 20 - 40% to obtain an extract;

[0146] (5) Take the above - mentioned extract, add 25% modified starch, mix evenly, and then dry it with a spray dryer. The inlet air temperature of the dryer is 160 - 205 °C, and the outlet air temperature is 70 - 100 °C to obtain a dry powder; sieve to obtain Rosa roxburghii powder.

[0147] Conclusion: Adding 25% modified starch to the preparation process and then performing spray drying is not conducive to the enrichment of vitamin C. Therefore, the content of vitamin C in the Rosa roxburghii powder prepared by this method is low, above 17%. This method is not suitable for enriching vitamin C.

[0148] Comparative Example 3:

[0149] Method source: The method of Comparative Document 3 "CN109232487A A method for extracting vitamin C from Rosa roxburghii" is adopted, and the steps are as follows:

[0150] (1) Grinding and enzymatic hydrolysis: First, wash, disinfect, and pulverize the air - dried Rosa roxburghii into 90 - 120 meshes, add water with a volume 1 time that of the Rosa roxburghii fruit, stir for 5 min, grind in a grinding tank with ethanol vapor and CO2 as protective gases for 6 min, add 0.05% composite enzyme based on the mass of the Rosa roxburghii fruit. The composite enzyme consists of two parts, A and B. A is cellulase, amylase, and protease, and B is superoxide dismutase. First add composite enzyme A, then composite enzyme B, continuously grind for 20 - 40 min, and sterilize for 5 - 8 min to obtain a Rosa roxburghii mixed material liquid;

[0151] (2) Extraction: Add tea saponin and chitosan to the sterilized Rosa roxburghii mixed material liquid, shake continuously for 10 min, then add 24% sodium chloride by concentration, centrifuge, and filter to obtain a clarified Rosa roxburghii permeate for standby;

[0152] (3) Separation and concentration: Add mixed acid to the clarified and permeated juice of Rosa roxburghii Tratt obtained in step 2, and use a separation membrane device for separation to obtain a permeate of the separation membrane. The separation membrane is an ultrafiltration membrane. Then use the ultrafiltration membrane device to concentrate the permeate of the separation membrane. Add alkali to neutralize the mixed acid in the concentrated solution to obtain a concentrated vitamin C solution, and freeze-dry it at -15°C to obtain crystals.

[0153] Conclusion: This method uses a relatively large variety of excipients, increasing the production cost. The grinding treatment step is applicable to dried Rosa roxburghii Tratt fruits. The preparation process is relatively complex. The vitamin C content in the product obtained by this method is 398 mg / g, which is relatively low. The process is relatively complex and not suitable for industrial production applications.

[0154] Experimental examples:

[0155] The inventors of the present invention conducted in vitro antioxidant function tests and whitening efficacy tests on the vitamin C-rich Rosa roxburghii Tratt extract prepared by the present invention. Some test contents are excerpted as follows:

[0156] I. In vitro antioxidant function test:

[0157] (1) DPPH free radical scavenging rate determination experiment

[0158] 1. Preparation of DPPH solution

[0159] Precisely weigh DPPH reagent and add absolute ethanol to prepare a 0.1 mmol / L DPPH solution, and store it in the dark and refrigerated. Preparation of sample solutions: Weigh 0.5 g, 0.4 g, 0.3 g, 0.2 g, 0.1 g, and 0.05 g of vitamin C-rich Rosa roxburghii Tratt extract, Rosa roxburghii Tratt juice, and positive control solution (containing 1 mg / mL of vitamin C) respectively, place them in 10 mL volumetric flasks, add distilled water to prepare solutions with different concentration gradients, and shake well for later measurement.

[0160] 2. Determination of DPPH scavenging rate of raw materials

[0161] Take 2 mL of each sample with different concentration gradients, add 2.0 mL of DPPH solution to each test tube, react in the dark at room temperature for 30 min, shake well, and measure the absorbance value. The absorbance value measured at 517 nm is recorded as A j ; Take 2 mL of each sample with various gradients, add 2.0 mL of distilled water to each test tube, and the absorbance value measured at 517 nm is recorded as A i .

[0162] The control group is 2 mL of DPPH solution plus 2 mL of distilled water, and its absorbance value is recorded as A c .

[0163] Use vitamin C solution with the same concentration as the positive control.

[0164] 3. Calculate the DPPH free radical scavenging rate (K) according to the following formula:

[0165]

[0166] The test results of the DPPH free radical scavenging ability of the vitamin C-rich Rosa roxburghii Tratt extract and Rosa roxburghii Tratt juice are shown in Table 2.

[0167] Table 2 Determination table of the DPPH free radical scavenging rate of the vitamin C-rich Rosa roxburghii Tratt extract

[0168]

[0169] Note: Compared with the vitamin C-rich Rosa roxburghii Tratt extract, *P < 0.05, **P < 0.01.

[0170] 4. Conclusion

[0171] The DPPH free radical scavenging ability of the vitamin C-rich Rosa roxburghii Tratt extract was significantly enhanced compared with that of Rosa roxburghii Tratt juice and the positive control vitamin C.

[0172] (2) Determination experiment of the ·OH free radical scavenging rate

[0173] 1. Preparation of stock solution

[0174] Precisely weigh salicylic acid and prepare a 10 mmol / mL solution with distilled water, denoted as stock solution A; precisely weigh ferrous sulfate and prepare a 10 mmol / mL solution with distilled water, denoted as stock solution B; precisely measure hydrogen peroxide and prepare a 100 mmol / mL solution with distilled water, denoted as stock solution C, and use it immediately after preparation; Preparation of test samples: Respectively take 0.5 g, 0.4 g, 0.3 g, 0.2 g, 0.1 g, 0.05 g of the vitamin C-rich Rosa roxburghii Tratt extract, Rosa roxburghii Tratt juice, and positive control solution (containing 1 mg / mL of vitamin C), place them in a 10 mL volumetric flask, and prepare solutions with different concentration gradients by adding distilled water, shake well and wait for measurement.

[0175] 2. Determination of the ·OH free radical scavenging rate of the vitamin C-rich Rosa roxburghii Tratt extract

[0176] Successively take 0.5 mL of each sample with different concentration gradients, add 0.5 mL of stock solution A, 0.5 mL of stock solution B, 3.5 mL of distilled water to each test tube, and finally add 5 mL of stock solution C to start the reaction. After shaking well, measure the absorbance value A at 510 nm m ; Take 0.5 mL of each sample with different concentration gradients, only add stock solution A and 4 mL of distilled water, and finally add 5 mL of stock solution C to start the reaction. After shaking well, also measure the absorbance value A at 510 nm n .

[0177] The control group had no sample solution. Only 0.5 mL of stock solution A, 0.5 mL of stock solution B, and 4 mL of distilled water were added, and then 5 mL of stock solution C was added. The absorbance value was recorded as A c .

[0178] A solution of vitamin C (hereinafter referred to as vitamin C) with the same concentration was used as the positive control

[0179] 3. Calculate the OH· radical scavenging rate (K) according to the following formula

[0180]

[0181] The test results of the OH· radical scavenging ability of the vitamin C-rich Rosa roxburghii Tratt extract and Rosa roxburghii Tratt juice are shown in Table 3

[0182] Table 3 Determination table of OH· radical scavenging rate of vitamin C-rich Rosa roxburghii Tratt extract

[0183]

[0184] Note: Compared with the vitamin C-rich Rosa roxburghii Tratt extract, *P<0.05, **P<0.01

[0185] 4. Conclusion

[0186] The OH· radical scavenging ability of the vitamin C-rich Rosa roxburghii Tratt extract was significantly enhanced compared with the positive control vitamin C and Rosa roxburghii Tratt juice

[0187] II. Whitening experiment (tyrosinase inhibition experiment)

[0188] 1. Detection conditions Tyrosinase catalyzes the formation of dopachrome from L-dopa, which has a characteristic absorption peak at 475 nm. In the presence of antioxidants, the production of dopachrome will be inhibited. Measuring the absorbance of dopachrome at 475 nm can determine and calculate the tyrosinase inhibition ability of the sample

[0189] 2. Extraction of tyrosinase Add 0.1 g of potato to 1 mL of extraction solution, homogenize and grind, and take the supernatant after centrifugation to obtain the tyrosinase extraction solution

[0190] 3. Sample solution preparation The Rosa roxburghii Tratt juice and the vitamin C-rich Rosa roxburghii Tratt extract were respectively diluted into sample solutions with different concentration gradients, and the total reaction system was 200 mL. Take 20 mL of each sample with different concentration gradients to be tested, and successively add 140 mL of reagent I and 20 mL of tyrosinase extraction solution. After reacting at 37°C for 10 min, measure its absorbance at 475 nm. The blank tube was replaced with purified water, and each sample was measured in parallel 3 times, with the vitamin C control solution as the positive control. Calculate the tyrosinase inhibition rate according to the formula, draw the correlation curve between the standard extract concentration gradient and the tyrosinase inhibition rate, and calculate the IC of the sample 50Compare the tyrosinase inhibitory ability of the juice of Rosa roxburghii tratt and the Rosa roxburghii tratt extract rich in vitamin C by the concentration (the concentration of the sample required to inhibit 50% of tyrosinase).

[0191] 4. Calculation formula

[0192] Tyrosinase inhibition rate % = [(A - B) - (C - D)] / (A - B) × 100

[0193] Where A is the absorbance value of the reaction system containing tyrosinase but no sample; B is the absorbance value of the reaction system containing no tyrosinase and no sample; C is the absorbance value of the reaction system containing tyrosinase and the sample; D is the absorbance value of the reaction system containing no tyrosinase but the sample.

[0194] The results of the tyrosinase inhibition test of the Rosa roxburghii tratt extract rich in vitamin C and the juice of Rosa roxburghii tratt are shown in Table 4.

[0195] Table 4 Determination table of tyrosinase inhibition rate of Rosa roxburghii tratt extract rich in vitamin C

[0196]

[0197] Note: Compared with the Rosa roxburghii tratt extract rich in vitamin C, *P < 0.05, **P < 0.01, Δ P > 0.05.

[0198] 5. Conclusion

[0199] The tyrosinase inhibition rate of the Rosa roxburghii tratt extract rich in vitamin C is significantly enhanced compared with that of the juice of Rosa roxburghii tratt, and there is an increasing trend compared with the positive control vitamin C.

[0200] Although the present invention has been described in detail by combining preferred embodiments and experimental examples, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, those of ordinary skill in the art can make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions should all be within the scope covered by the present invention. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A preparation method of a Rosa roxburghii Tratt extract rich in vitamin C, characterized in that It includes the following steps: (1) Wash the fresh Rosa roxburghii fruits, freeze them at -4 to -20 °C for more than 24 hours. Take out the frozen fresh Rosa roxburghii fruits, after thawing, juice them at a pressure of 3 to 7 kg for 0.5 to 1.5 hours, and filter to obtain Rosa roxburghii juice; (2) Take the Rosa roxburghii juice, dilute it with purified water with a volume 1 to 7 times that of the Rosa roxburghii juice, and filter it through a 10 to 100 KD ultrafiltration membrane to obtain a filtrate; (3) Take the filtrate, control the pressure at 1 to 6 kg, and concentrate it with a reverse osmosis membrane to obtain concentrated Rosa roxburghii juice; (4) Take the concentrated Rosa roxburghii juice, add ethanol with a mass 8 to 12 times that of the concentrated Rosa roxburghii juice and with a concentration of 80 to 95%, stir well, place it at 2 to 8 °C for 10 to 16 hours, centrifuge to take the supernatant, and concentrate the supernatant under reduced pressure with a vacuum degree of 0.08 to 0.09 mpa and a concentration temperature of 40 to 55 °C to obtain an alcohol-precipitated concentrated solution; (5) Take the alcohol-precipitated concentrated solution and load it onto AB-8 or HPD-100 or D101 macroporous resin, use purified water or an aqueous solution containing 5 to 30% ethanol as the eluent, and concentrate the eluate to an extract paste with a relative density of 1.10 to 1.20; (6) The extract paste is subjected to vacuum drying: with a vacuum degree of 0.08 to 0.09 mpa and a drying temperature of 40 to 55 °C; or freeze drying: with a pre-freezing temperature of -10 to 50 °C, a vacuum degree of 10 to 30 Pa, a water trap temperature of 35 to 45 °C, and a partition temperature of -10 to 10 °C to obtain a Rosa roxburghii extract rich in vitamin C.

2. The preparation method of the rose roxburghii tratt extract rich in vitamin C according to claim 1, wherein: In the step (1), the freezing temperature is -12 °C, the juicing pressure is 5 kg, and the juicing time is 1 hour.

3. The preparation method of the rosa roxburghii tratt extract rich in vitamin C according to claim 2, wherein: In the step (2), it is diluted with purified water with a volume 4 times that of the Rosa roxburghii juice and filtered through a 50 KD ultrafiltration membrane.

4. The preparation method of the rose roxburghii tratt extract rich in vitamin C according to claim 3, characterized in that: In the step (3), the pressure is controlled at 3 kg.

5. The preparation method of the Rosa roxburghii tratt extract rich in vitamin C according to claim 4, characterized in that: In the step (4), 10 times the amount of 85% ethanol is used, alcohol precipitation is carried out at 6 °C for 13 hours, the vacuum degree for ethanol recovery is 0.085 mpa, and the concentration temperature is 43 °C.

6. The preparation method of the Rosa roxburghii Tratt extract rich in vitamin C according to claim 5, characterized in that: In the step (5), the macroporous resin is HPD-100, and it is eluted with purified water as the eluent, and the eluate is concentrated to an extract paste with a relative density of 1.

15.

7. The preparation method of the rosa roxburghii tratt extract rich in vitamin C according to claim 6, characterized in that: In the step (6), the extract paste is vacuum dried with a vacuum degree of 0.085 mpa and a drying temperature of 47 °C.

8. The Rosa roxburghii extract rich in vitamin C prepared by the preparation method according to any one of claims 1 to 7, wherein the vitamin C content in the extract is ≥ 50%.

9. Use of the Rosa roxburghii extract rich in vitamin C according to claim 8 in the preparation of antioxidant and whitening products.

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